I'm not necessarily confused, I was just under the impression that a Walbro 255 would suffice for my set-up with no RFS and 440cc's. (Sentry's FAQ on Vortech superchargers) https://my350z.com/forum/forced-indu...questions.html

 

the pump is fine. without a RFS, you drop your fuel pressure by the same amount you are boosting.

So if you start with 50psi at idle and make 12psi of boost, your fuel pressure might be as low at 38psi at WOT. So not only do you have too small injectors you now also have inadequate fuel pressure.

 

Ok I see, in your opinion what should I do from here? Man, I relied waaaay to much on the search function on other people's similar set up to mine and it's biting me in the butt.

 

Btw, I found my dyno sheet and I guess it's a DYNOmite?

 

just get a set of 600cc injectors. you can sell yours to offset most of the cost

 

Sounds good I'll order some DW 600's and post up new dyno #'s soon. This might be a dumb question and it's unrelated, but if I adjust my bypass valve before my next tune to 6 threads instead of 10 showing will I need a re-tune because I would be building boost sooner?

 

NO! Leave the Factory Setting alone.

It's set to close around 10 in Vac.

Why change it?

 

A lot of people have stated that 6-7 threads showing on the Vortech bypass valve would be as follows. (Instead of the factory 10 threads showing). I figured it was best asking and not assuming anything. I like my sleep at night haha.

"The stock setting doesn't allow the valve to close (ie allow you to start boosting) until you're around zero vacuum. set the screw so that only 6-7 screws are showing and you'll start building boost a little sooner."

 

Welp, I installed some DW600cc's and have the DW440cc's I removed for sale in the marketplace. Got it dyno tuned a couple of days ago at Element Racing here in Utah again with the same tuner as before. I didn't come close to my goal of 400whp, but to say I have a legit car with 400bhp+ isn't bad either . The weather sucks outside, so I have not taken her out for a joy ride just yet. Thoughts are appreciated.

 

Sorry to wake the dead on this post, but i was also having the same issue with my build, ended up getting 332whp off of my 3.12 pulley. had 500cc injectors and walbro fuel pump and yielded the same results as you, OP. I picked up some 720cc Injectors today hoping to retune soon, also bought the GTM Pulley Set to help eliminate some belt slip cause i wan also only making 5.5 psi on the dyno. =/